Formerly, the last of the three meals of the day (breakfast, dinner, and supper); now applied to the last substantial meal of the day when dinner is taken in the middle of the day, or to a late meal following an early evening dinner. Supper is usually a less formal meal than late dinner.
My guess would be food after a late work shift, so probably working class
southern parents who lived for some time in the north, evening meal was still dinner but came with the offer of ‘sauce or owt?’ pronounced something like saucer aaht
IIRC this is a class divide indicator. The fact that class maps well onto geography is just correlation.
Middle class has breakfast, lunch, and dinner.
Working class has breakfast, dinner, and tea.
Supper is an outlier and definitely more unusual. In my experience it usually indicates a smaller evening meal.
https://www.etymonline.com/word/supper
My guess would be food after a late work shift, so probably working class
if you call dinner the main meal of the day, the earlier you start work, the earlier you’ll have it
southern parents who lived for some time in the north, evening meal was still dinner but came with the offer of ‘sauce or owt?’ pronounced something like saucer aaht